System and method for redirecting control of in-band signaling

ABSTRACT

In a telecommunication system having a network switch capable of independently controlling inbound and outbound call legs, a system for, and method of, redirecting in-band control of signaling pertaining to a call placed by a calling party and a system for providing automatic call completion from the calling party to a called party. The control redirecting system includes: (1) call control circuitry, associated with the network switch, for routing the call from the calling party to another party through the network switch, the call thereby having an inbound leg from the calling party to the network switch and an outbound leg from the network switch to the other party and (2) call control redirection circuitry for treating the outbound leg of the call as a second inbound leg from the other party to the network switch and monitoring in-band control signals received from the other party via the second inbound leg. The call control redirection circuitry thereby allows the other party to issue the in-band control signals to the call control circuitry.

This application is a continuation of U.S. patent application Ser. No.08/586,021 filed on Dec. 29, 1995 now U.S. Pat. No. 6,314,175 B1, whichis hereby incorporated by reference in its entirety.

TECHNICAL FIELD OF THE INVENTION

The present invention is directed, in general, to telecommunicationsystems and, more specifically, to a system and method for redirectingcontrol of in-band signaling functions from the calling party to a partyother than the calling party.

BACKGROUND OF THE INVENTION

For years, the party placing a telephone call (the “calling party”) hasbeen primarily responsible for initiating the pulses, tones or othersignaling codes that cause telephone network equipment, such asswitches, to route the calling party's call through a telephone networkto a desired destination. In other words, signaling control has restedin the hands of the calling party. To date, the only exception to this.rule has been a telephone operator (or, synonymously, “attendant”), whohas been allowed to exert unique signaling control over the callingparty's call by virtue of special signaling connections between theattendant and the telephone equipment.

It is best to convey this traditional relationship by way of example. Acalling party wishing to place a call must first take a telephoneinstrument off-hook. The calling party must then dial or press digitscorresponding to the destination number (“DTN”) desired, thereby causingthe telephone instrument to generate pulses or tones (“controlsignals”)to direct the telephone equipment to place the call through thenetwork. If any further digits are required to complete the call, thecalling party has been responsible for supplying the digits whenprompted.

If the calling party does not know the DTN (and therefore requiresdirectory assistance) or needs other help (such as conferencing orinternational access), the calling party has been required to call thetelephone operator to employ the operator's assistance to find the DTNor complete the call. Again, the operator's special signalingconnections with the telephone equipment have given the operator thesignaling control required to perform these functions.

While this arrangement has been suitable in the past, it has becomeparticularly disadvantageous in today's telephony world. First, thetelephone network itself has become vastly more complicated. As computersystems have been integrated into the network, calling parties havefound themselves entering digits to navigate through menus, traverseprivate branch exchanges (“PBXs”), place their own international callsor access new services, such as electronic banking by phone or voicemailboxes. Today's telephone calls often resemble a computer sessionmore than they do a person-to-person conversation.

Second, it is becoming apparent that large, centralized attendantcenters staffed with banks of attendants are expensive to operate. Ofcourse, such centers have been necessary in the past, because theyrequired special signaling connections with, and therefore proximity to,the telephone equipment. However, it would be advantageous to providethe same or better level of customer service by means of a moreeconomical alternative.

Third, some parties are more experienced, better located or betterequipped than others to perform signaling functions. For instance, acalling party may wish to participate in, and pay for, a conferencecall, but has no idea how to generate the control signals to establishone. Apart from enlisting an attendant (at some cost), the calling partycurrently has no alternative but to muddle through the conferencingprocedure personally.

Accordingly, what is needed in the art is a way of eliminating the needfor the special signaling connections that are currently required toallow a party other than the calling party to control the signaling forthe calling party's call.

SUMMARY OF THE INVENTION

If such signaling could be performed over an ordinary voice channel,today's centralized “attendant centers” could then become virtual, withthe attendants being geographically distributed, perhaps even performingtheir jobs from their homes. Further, parties other than operators couldcontrol signaling and thereby “step into the shoes” of calling parties,allowing more capable, better located or better equipped parties tocontrol signaling for calls they themselves did not originate.

To address this objective and therefore overcome the above-discusseddeficiencies of the prior art, the present invention provides, in atelecommunication system having a network switch capable ofindependently controlling inbound and outbound call legs, a system for,and method of, redirecting in-band control of signaling pertaining to acall placed by a calling party and a system for providing automatic callcompletion from the calling party to a called party.

The control redirecting system includes: (1) call control circuitry,associated with the network switch, for routing the call from thecalling party to another party through the network switch, the callthereby having an inbound leg from the calling party to the networkswitch and an outbound leg from the network switch to the other partyand (2) call control redirection circuitry for treating the outbound legof the call as a second inbound leg from the other party to the networkswitch and monitoring in-band control signals received from the otherparty via the second inbound leg, the call control redirection circuitrythereby allowing the other party to issue the in-band control signals tothe call control circuitry.

The present invention therefore introduces the broad concept of allowinga party other than the calling party to issue in-band control signals orcommands to the call control circuitry. This allows the other party to“step into the shoes” of the calling party with respect to signaling viaa simple voice channel (the second inbound leg). Since the presentinvention allows redirection of control via a voice channel, the otherparty needs no special connection with, or proximity to, the networkswitch.

For purposes of the present invention, “in-band” is defined as beingwithin a voice channel (carried over, for example, an analog householdtelephone line, or such as an Integrated Services Digital Network(“ISDN”)B-channel), as opposed to a signaling or control channel (suchas an ISDN D-channel or a Signaling System 7 (“SS7”) channel). In otherwords, -in-band control signals traverse the same channel (or “band”)asthe substantive voice, video or computer data exchanged between thecalling and other parties.

In one embodiment, the present invention allows the other party to takecontrol over signaling upon the issuance of a particular control signal.For purposes of the present invention, “signaling” is broadly defined toinclude any signaling, call processing, call progress or call controlfunction.

In one embodiment of the present invention, the other party is a partyother than a called party, the system allowing the other party tocomplete a call from the calling party to the called party. In a morespecific embodiment to be described hereinafter, the present inventionenables automatic call completion, whereby an operator (or attendant)may assume control over the signaling functions of a calling party'scall. Automatic call completion allows the attendant to complete thecalling party's call without requiring the calling party to exertcontrol over the signaling. Alternatively, the other party is the calledparty itself, the system allowing the called party to issue the in-bandcontrol signals to the call control circuitry.

In one embodiment of the present invention, the system further comprisesa voice response unit (“VRU”), associated with the call controlcircuitry, for receiving in-band voice commands issued from the otherparty. Alternatively or additionally, the in-band control signals aredual-tone multifrequency (“DTMF”)commands. In-band signaling of anytype, however, is within the scope of the present invention.

In one embodiment of the present invention, the call control circuitryplaces the calling party on hold while the other party issues thein-band control signals to the network switch. By placing the callingparty on hold, this embodiment frees the calling party from having tohear any in-band signaling. Furthermore, the network switch is caused toignore any spurious in-band control signals that the calling party maygenerate. Control is thereby vested solely in the other party.

In one embodiment of the present invention, the call control circuitryallows the calling party to monitor the outbound leg while the otherparty issues the in-band control signals to the network switch. In thisembodiment, the calling party can hear the in-band control signals and,more specifically, the progress of the call. As in the previousembodiment, the network switch may be caused to ignore any spuriousin-band control signals that the calling party may generate.

In one embodiment of the present invention, the call control circuitrydrops the other party from the call after the other party issues thein-band control signals to the network switch. In this manner, the otherparty may interject in-band control signals for a period of time, andthen be dropped from the call. Dropping may occur upon the other party'sissuance of a particular control signal.

The foregoing has outlined, rather broadly, alternative embodiments andfeatures of the present invention so that those skilled in the art maybetter understand the detailed description of the invention thatfollows. Additional features of the invention will be describedhereinafter that form the subject of the claims of the invention. Thoseskilled in the art should appreciate that they can readily use thedisclosed conception and specific embodiment as a basis for designing ormodifying other structures for carrying out the same purposes of thepresent invention. Those skilled in the art should also realize thatsuch equivalent constructions do not depart from the spirit and scope ofthe invention in its broadest form.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present invention, reference isnow made to the following descriptions taken in conjunction with theaccompanying drawings, in which:

FIG. 1 illustrates an isometric view of a computer system that providesan environment within which the present invention can operate;

FIG. 2 illustrates a schematic block diagram of the central processingunit (“CPU”)of FIG. 1;

FIG. 3 illustrates a telecommunication system employing an embodiment ofa system for redirecting control of in-band signaling according to theprinciples of the present invention;

FIG. 4 illustrates a method for redirecting control of in-band signalingaccording to the principles of the present invention;

FIG. 5 illustrates a telecommunication system employing an embodiment ofa call completion system according to the principles of the presentinvention; and

FIG. 6 illustrates a representative method of completing a callaccording to the principles of the present invention.

DETAILED DESCRIPTION

Referring initially to FIG. 1, illustrated is an isometric view of acomputer system 100 that provides an environment within which thepresent invention can operate. Since the present invention is notlimited to application in a computer environment, however, FIG. 1 ispresented for illustrative purposes only.

The computer system 100 includes a monitor 110, a chassis 120 and akeyboard 130. The monitor 110 and the keyboard 130 cooperate to allowcommunication between the computer system 100 and a user. Alternatively,the monitor 110 and keyboard 130 may be replaced by other conventionaloutput input devices, respectively. The chassis 120 includes both afloppy disk drive 140 and hard disk drive 145. The floppy disk drive 140is employed to receive, read and write to removable disks; the hard diskdrive 145 is employed for fast access storage and retrieval, typicallyto a nonremovable disk. The floppy disk drive 140 may be replaced by orcombined with other conventional structures to receive and transmit dataand instructions, including without limitation, tape and compact discdrives, telephony systems and devices (including videophone, paging andfacsimile technologies), and serial and parallel ports.

The chassis 120 is illustrated having a cut-away portion that includes abattery 150, clock 160, central processing unit (“CPU”) 170 and memorystorage device 180. The call control circuitry, call control redirectioncircuitry and call placement circuitry of the present invention are, inthe illustrated embodiments, formed by a cooperation of the CPU 170, thememory storage device 180 and a sequence of executable instructions,storable in the memory storage device 180 and executable in the CPU 170to perform as specified. Although the computer system 100 is illustratedhaving a single CPU 170, hard disk drive 145 and memory storage device180, the computer system 100 may be equipped with a plurality of CPUsand peripheral devices.

It should be noted that any conventional computer system having at leastone CPU that is suitable to function at a network switch or attendantcenter system may be replaced, or be used in conjunction with, thecomputer system 100, including without limitation: videophones,telephones, televisions, sophisticated calculators, and hand-held,laptop/notebook, mini, mainframe and supercomputers, including RISC andparallel processing architectures, as well as within computersystem/network combinations. Conventional computer system architectureis more fully discussed in Computer Organization and Architecture, byWilliam Stallings, MacMillan Publishing Co. (3rd ed. 1993), incorporatedherein by reference. Alternative computer system embodiments may befirmware-or hardware-based.

Turning now to FIG. 2, illustrated is a schematic block diagram of theCPU 170 of FIG. 1. The CPU 170 is coupled to the memory storage device180 by a data bus 210. The memory storage device 180 stores data andinstructions that the CPU 170 uses to execute the functions necessary tooperate the computer system 100. The memory storage device 180 may beany conventional memory storage device. The CPU 170 includes a controlunit 220, arithmetic logic unit (“ALU”) 230 and local memory storagedevice 240 (e.g. stackable cache or a plurality of registers). Thecontrol unit 220 fetches the instructions from memory storage device180. The ALU 230, in turn, performs a plurality of operations, includingaddition and Boolean AND, necessary to carry out the instructionsfetched from the memory storage device 180. The local memory storagedevice 240 provides a local high speed storage location for storingtemporary results and control information generated and employed by theALU 230. Again, the call control circuitry or call placement circuitryof the present invention is embodied in the CPU 170 in combination withthe memory storage device 180.

Turning now to FIG. 3, illustrated is a telecommunication system (e.g.,the public telephone network) employing an embodiment of a system forredirecting control of in-band signaling according to the principles ofthe present invention. The system, designated 300, comprises aconventional network switch 310 coupled to a plurality of conventionaltelephone lines 320. The plurality of telephone lines 320 are coupled toa plurality of endpoints or, more generally, nodes (only two of whichare shown) within the system 300, allowing the network switch 310 toprovide circuit switching among the plurality of endpoints or nodes.First and second endpoints 330, 340 are illustrated and happen to be,for the purposes of the present discussion, telephone instruments. Alsofor purposes of the present discussion, the first endpoint 330 isassociated with a calling party (not shown) and the second endpoint 340is associated with another party (again, not shown).

Call control circuitry 350 is coupled to, and controls, the networkswitch 310. In the illustrated embodiment, the network switch 310 isprocessor-controlled; the call control circuitry 350 therefore takes theform of a sequence of computer-executable instructions executed in the,processor of a general purpose computer (such as the computer system 100of FIG. 1) to cause the conventional network switch 310 operate in anovel manner according to the present invention. Of course, the callcontrol circuitry (and the call control redirection circuitry and callplacement circuitry, for that matter) may take the form of hard-wireddigital or analog circuitry, as appropriate.

During its normal operation, the network switch 310 couples “inbound”legs (telephone lines coupled to endpoints belonging to calling parties)to “outbound” legs (telephone lines coupled to endpoints belonging tocalled parties). In this manner, calling and called parties are linkedtogether for point-to-point communication of the parties' substantivevoice, video or computer data. Normally, inbound and outbound legs arecarried on a single physical channel within the network switch 310 or ontwo inseparably linked physical channels.

However, in some conventional network switches, particularlyprocessor-controlled switches such as the commercially-availableDEFINITY” switch manufactured by AT&T, it is possible to separate theinbound and outbound legs of a given call and control each legindependently. Although it has always been known that conventionalnetwork switches may be modified to separate the individual legs of agiven call, there has been no motivation to modify a network switch toseparate the legs, until now. In fact, under normal circumstances, itwould be disadvantageous to separate the legs of a call, since suchmight disconnect the call.

Separation of the call legs, however, is important to the presentinvention, as it allows the call control circuitry 350 to treat theoutbound leg of a given call as a second inbound leg without disturbingthe original inbound leg. This gives the party corresponding to thenewly-designated second inbound leg complete control over signalingfunctions that would have previously only been vested in the callingparty via the original inbound leg.

Accordingly, FIG. 3 shows call control redirection circuitry 360,coupled to the call control circuitry 350 and the network switch 310.The call control redirection circuitry 360 is capable of monitoringcalls passing through the network switch 310 for particularredirection-enabling control signals. The nature of these and othersignals will be described in detail hereinafter.

FIG. 3 further shows an optional VRU 370. The VRU 370 is coupled to thecall control circuitry 350 and is capable of intercepting voice commandsfrom calls passing through the network switch 310. It should beunderstood that the VRU 370 is shown for completeness and is notnecessary to the present invention. In the absence of a VRU 370, DTMF orother in-band signals may still be used to effect signaling control. Itshould also be understood that the system 300 may further compriseother, perhaps intermediate, nodes, such as routers. The presence orabsence of such other nodes would not affect the operation of thepresent invention and are therefore omitted from FIG. 3 for clarity'ssake.

The operation of the system 300 to effect redirection of control ofin-band signaling will now be described. Turning now to FIG. 4,illustrated is a method for redirecting control of in-band signalingaccording to the principles of the present invention. The method beginswith a start step 400, wherein a calling party has made a call with thefirst endpoint 330 through the network switch 310 and under control ofthe call control circuitry 350. The calling party may have intentionallyplaced the call to the other party at the second endpoint 340.Alternatively, the calling party may have attempted, unsuccessfully, toplace the call to an unnamed called party at a third endpoint (notshown) and have been routed automatically by the network switch 310 tothe other party at the second endpoint 340. Alternatively, the networkswitch 310 may have routed the call automatically to the other party,even though the calling party properly placed the call to the unnamedcalled party (perhaps if the call is international). In either case, thenetwork switch 310 routes the call to the other party at the secondendpoint 340. At this point in the call, the calling party has completecontrol of signaling functions.

In a monitor call step 410, the call control redirection circuitry 360monitors the call for particular in-band control signals that are toactivate redirection of call control. For purposes of the presentdiscussion, it will be assumed that the particular in-band controlsignal is a DTMF tone corresponding to “#”,a key found on conventionaltelephone key pads. (If a VRU 370 is present, the activating in-bandcontrol signal could be a spoken word or series of words.) If the callcontrol redirection circuitry 360 detects the “#” DTMF tone, the callredirection circuitry 360 directs the network switch 310 to separate theinbound leg (from the first endpoint 330 associated with the callingparty) from the outbound leg (to the second endpoint 340 associated withthe other party) in a step 420.

Once separated, the call control redirection circuitry 360 directs thecall control circuitry to treat the outbound leg as a second inbound legin a step 430, preferably without affecting the original inbound leg inany way. The call control redirection circuitry 360 may optionally placethe original inbound leg on hold (to free the calling party from havingto hear the subsequent in-band signaling) or may allow the originalinbound leg to continue to monitor the in-band signaling. In eithercase, it is advantageous that the call control redirection circuitry 360direct the network switch 310 to ignore any spurious in-band controlsignals that the calling party may thereafter inadvertently orintentionally generate. By ignoring any such control signals, thenetwork switch 310 is prevented from being confused or misdirected byvirtue of being under control of more than one party at a time.

In a step 440, the call control circuitry 350 begins to accept andperform according to in-band control signals from the other party viathe second endpoint 340. Again, the in-band control signals may take theform of voice commands routed through the VRU 370 or may take the formof DTMF tones. The other party may direct the call control circuitry 360to perform any function that the calling party could have commanded. Theother party, if properly authorized, may even have access to functionsnot available to the calling party (e.g., functions that would only beproper to make available to an operator). Such might be desirable if,for instance, the other party is an attendant and is performingfee-based services on behalf of the calling party.

The present invention can further allow the other party to redirectbilling for the call. This is particularly desirable if, again, theother party is an attendant. Through the use of in-band control signals,the other party can select whether the calling party, a called party,the other party or some third party (such as a corporate account) isultimately billed for the call (or, for that matter, the fee-basedservices).

In a step 450, it is assumed that the other party wishes to relinquishcontrol of the call. Preferably, the other party relinquishes control byissuing another particular terminating control signal (perhaps a DTMFtone corresponding to a “*”) to the call control redirection circuitry360. When the call control redirection circuitry 360 receives suchcontrol signal, the call control redirection circuitry 360 may directthe network switch 310 to reconnect the original inbound and outboundlegs to restore the call between the calling and other parties. (In thisexample, the network switch 310 has redesignated the outbound leg atotal of two times.) Alternatively, the call control redirectioncircuitry 360 may direct the network switch 310 to connect the inboundleg with another outbound leg that the other party may have createdwhile interacting with the call control circuitry 350. This isparticularly appropriate in automatic call completion, wherein the otherparty (often an attendant) may place a second call (on behalf of thecalling party) to a called party and may, through the call controlredirection circuitry 360, cause the inbound leg of the first call fromthe calling party to be joined to the outbound leg of the second call tothe called party. Automatic call completion will be described mostparticularly with respect to FIGS. 5 and 6.

Having relinquished control, the call control redirection circuitry 360may, under some circumstances, drop the other party from the call. Themethod then ends in an end step 460.

Turning now to FIG. 5, illustrated is the telecommunication system 300employing an embodiment of a call completion system according to theprinciples of the present invention. Automatic call completion via adirectory assistance service is a well-known feature that telephonecompanies currently offer. The directory assistance service typicallyenables a calling party to request and obtain automatic completion of acall to a called party at a DTN by simply pressing a button on atouchtone telephone. In response, the directory assistance servicedirects the telecommunication system to which it is directly linked todial the DTN and thereby complete the call automatically.

Because the calling party is not directly involved in completing thecall, automatic call completion frees the calling party from the need tomemorize or write down the DTN (required in manual call completion) andresults in a substantially faster connection to the called party thanmanual call completion. As previously described, one of the applicationsof the present invention is to effect automatic call completion, whereina more experienced, better located or better equipped attendant (orother party) may complete a call on behalf of a calling party (1)without requiring the calling party to intervene and (2) withoutrequiring a special signaling path between the attendant (or otherparty) and the network switch.

Returning to FIG. 5, the telecommunication system 300 includes thenetwork switch 310 coupled to the plurality of conventional telephonelines-320. The plurality of conventional telephone lines 320 are coupledto the plurality of endpoints, allowing the network switch 310 toprovide circuit switching among the plurality of endpoints. The firstendpoint 330 and a third endpoint 520 are illustrated and happen to be,for the purposes of the present discussion, telephone instruments. Alsofor purposes of this discussion, the first endpoint 330 is associatedwith a calling party (not shown) and the third endpoint 520 isassociated with a called party (again, not shown). The telecommunicationsystem 300 also includes an attendant center system or global customerservices center (“GCSC”) 530 coupled to the network switch 310 via asecond endpoint 510 and having call placement circuitry 540 associatedtherewith. The call placement circuitry 540 generates in-band DTN datacontrol signals to direct the call control circuitry 350 to place callsthrough the telecommunication network 300. The call placement circuitry540 may simply receive and forward DTMF codes or voice commands from anattendant and may actually form a portion of the second endpoint 510 ormay be an automated operator capable of completing calls and therefore aseparate piece of equipment (as shown)

Again, the call control circuitry 350 is coupled to, and controls, thenetwork switch 310. Again, during its normal operation, the networkswitch 310 couples “inbound” legs (telephone lines coupled to endpointsbelonging to calling parties) to “outbound” legs (telephone linescoupled to endpoints belonging to called parties).

The call control redirection circuitry 360 is again illustrated as beingcoupled to the call control circuitry 350 and the network switch 310. Asin FIG. 3, the call control redirection circuitry 360 is capable ofmonitoring calls passing through the network switch 310 for particularredirection-enabling control signals. FIG. 5 further shows the optionalVRU 370. The VRU 370 is coupled to the call control circuitry 350 and iscapable of intercepting voice commands from calls passing through thenetwork switch 310. As in FIG. 3, it should be understood that the VRU370 is shown for completeness and is not necessary to the presentinvention. In the absence of a VRU 370, DTMF or other in-band signalsmay still be used to effect signaling control. The operation of thesystem 300 to effect redirection of control of in-band signaling willnow be described.

Turning now to FIG. 6, illustrated is a representative method ofcompleting a call according to the principles of the present invention.The method begins with a start step 600, wherein a calling party hasmade a call via the first endpoint 330 through the network switch 310and under control of the call control circuitry 350. Whether the callingparty has intended so or not, the network switch 310 routes the call tothe GCSC 530 at the second endpoint 510. At this point in the call, thecalling party has complete control of signaling functions.

In a monitor call step 610, the call control redirection circuitry 360monitors the call for particular in-band control signals that are toactivate redirection of call control. Again, for purposes of the presentdiscussion, it will be assumed that the particular in-band controlsignal is a DTMF tone corresponding to “#”, a key found on conventionaltelephone key pads. (If the VRU 370 is present, the activating in-bandcontrol signal could be a spoken word or series of words.) If the callcontrol redirection circuitry 360 detects the “#” DTMF tone, the callredirection circuitry 360 directs the network switch 310 to separate theinbound leg (from the first endpoint 330 associated with the callingparty) from the outbound leg (to the second endpoint 510 associated withthe GCSC 530) in a step 620.

Once separated, the call control redirection circuitry 360 directs thecall control circuitry to treat the outbound leg as a second inbound legin a step 630, preferably without affecting the original inbound leg inany way. The call control redirection circuitry 360 may optionally placethe original inbound leg on hold (to free the calling party from havingto hear the subsequent in-band signaling) or may allow the originalinbound leg to continue to monitor the in-band signaling. In eithercase, it is advantageous that the call control redirection circuitry 360direct the network switch 310 to ignore any spurious in-band controlsignals that the calling party may thereafter inadvertently orintentionally generate. By ignoring any such control signals, thenetwork switch 310 is prevented from being confused or misdirected byvirtue of being under control of more than one party at a time.

In a step 640, the call control circuitry 350 begins to accept andperform according to in-band control signals from the call placementcircuitry 540 at the GCSC 530 via the second endpoint 510. Again, thein-band control signals may take the form of voice commands routedthrough the VRU 370 or may take the form of DTMF tones. The GCSC 530 maydirect the call control circuitry 360 to complete the call to the calledparty via the third endpoint 520 according to the calling party'sinstructions.

In a step 650, it is assumed that, after completing the call, the GCSC530 wishes to relinquish control of the call. Preferably, the GCSC 530relinquishes control by issuing another particular terminating controlsignal (perhaps a DTMF tone corresponding to a “*”) to the call controlredirection circuitry 360. When the call control redirection circuitry360 receives such a control signal, the call control redirectioncircuitry 360 directs the network switch 310 to connect the inbound legwith the outbound leg that the GCSC 530 created when completing the callon behalf of the calling party.

Having relinquished control, the call control redirection circuitry 360advantageously drops the GCSC 530 from the call. The method then ends inan end step 660. Either the calling party or the called party mayterminate the call after the GCSC 530 is dropped therefrom.

Although the present invention has been described in detail, thoseskilled in the art should understand that they can make various changes,substitutions and alterations herein without departing from the spiritand scope of the invention in its broadest form.

What is claimed is:
 1. In a telecommunication system having a networkswitch capable of independently controlling inbound and outbound calllegs, a system for redirecting in-band control of signaling pertainingto a call placed by a calling party, comprising: call control circuitry,associated with said network switch, for routing a first call from saidcalling party to another party through said network switch, said callthereby having an inbound leg from said calling party to said networkswitch and an outbound leg from said network switch to said other party;call control redirection circuitry for treating said outbound leg ofsaid first call as a second inbound leg from said other party to saidnetwork switch and monitoring in-band control signals received from saidother party via said second inbound leg, said call control redirectioncircuitry thereby allowing said other party to issue said in-bandcontrol signals to said call control circuitry; and wherein said otherparty is a party other than a called party, said system allowing saidother party to complete a call from said calling party to said calledparty.
 2. The system as recited in claim 1 further comprising a voiceresponse unit (VRU), associated with said call control circuitry, forreceiving in-band voice commands issued from said other party.
 3. Thesystem as recited in claim 1 wherein said in-band control signals aredual-tone multifrequency (DTMF) commands.
 4. The system as recited inclaim 1 wherein said call control circuitry places said calling party onhold while said other party issues said in-band control signals to saidnetwork switch.
 5. The system as recited in claim 1 wherein said callcontrol circuitry allows said calling party to monitor said outbound legwhile said other party issues said in-band control signals to saidnetwork switch.
 6. The system as recited in claim 1 wherein said callcontrol circuitry drops said other party from said call after said otherparty issues said in-band control signals to said network switch.
 7. Ina telecommunication system having a network switch capable ofindependently controlling inbound and outbound call legs, a method ofredirecting in-band control of signaling pertaining to a call placed bya calling party, comprising: routing said call from said calling partyto another party through said network switch, said call thereby havingan inbound leg from said calling party to said network switching andoutbound leg from said network switch to said other party; treating saidoutbound leg of said call as a second inbound leg from said other partyto said network switch; monitoring in-band control signals received fromsaid other party via said second inbound leg, thereby allowing saidother party to issue said in-band control signals to said networkswitch; and wherein said other party is a party other than a calledparty, said method allowing said other party to complete a call fromsaid calling party to said called party.
 8. The method as recited inclaim wherein said monitoring includes receiving in-band voice commandsissued from said other party.
 9. The method as recited in claim 7wherein said in-band control signals are dual-tone multifrequency (DTMF)commands.
 10. The method as recited in claim 7 further comprising thestep of placing said calling party on hold while said other party issuessaid in-band control signals to said network switch.
 11. The method asrecited in claim 7 further comprising the step of allowing said callingparty to monitor said outbound leg while said other party issues saidin-band control signals to said network switch.
 12. The method asrecited in claim 7 further comprising the step of dropping said otherparty from said call after said other party issues said in-band controlsignals to said network switch.
 13. In a telecommunication system havinga processor-controlled network switch capable of separating inbound andoutbound call legs and an attendant center system coupled thereto, acall completion system for providing automatic call completion from acalling party to a called party, comprising: call control circuitry,associated with said network switch, for routing a first call from saidcalling party to said attendant center system through said networkswitch and monitoring in-band control signals received from saidattendant center system; and call placement circuitry, associated withsaid attendant center system, for generating in-band destination numberdata control signals and to direct said call control circuitry to placea second call to said called party through said telecommunicationsystem, said call control circuitry subsequently merging said first andsecond calls to couple said calling party to said called party throughsaid telecommunication system, said call control circuitry placing saidsecond call.
 14. The call completion system as recited in claim 13further comprising a voice response unit (VRU), associated with saidcall control circuitry, for receiving in-band voice commands issued viasaid attendant center system.
 15. The call completion system as recitedin claim 13 wherein said call control circuitry places said first callon hold while said call control circuitry places said second call tosaid called party through said network switch.
 16. The call completionsystem as recited in claim 13 wherein said call control circuitry allowssaid calling party to monitor an inbound call leg of said first callwhile said call control circuitry places said second call to said calledparty through said network switch.
 17. The call completion system asrecited in claim 13 wherein said attendant center system transmits saidcontrol signals to said call control circuitry via an outbound call legof said First call.
 18. The call completion system as recited in claim13 wherein said call control circuitry drops said attendant centersystem from said first call after said call control circuitry mergessaid first and second calls to couple said calling party to said calledparty through said network switch.
 19. The call completion system asrecited in claim 13 wherein said call control circuitry places saidsecond call to said called party through said network switch.
 20. In atelecommunication system having a network switch capable ofindependently controlling inbound and outbound call legs, a system forredirecting in-band control of signaling pertaining to a call placed bya calling party, comprising: call control circuitry, associated withsaid network switch, for routing a first call from said calling party toanother party through said network switch, said call thereby having aninbound leg from said calling party to said network switch and anoutbound leg from said network switch to said other party; call controlredirection circuitry for treating said outbound leg of said first callas a second inbound leg from said other party to said network switch andmonitoring in-band control signals received from said other party viasaid second inbound leg, said call control redirection circuitry therebyallowing said other party to issue said in-band control signals to saidcall control circuitry; and wherein said call control circuitry allowssaid calling party to monitor said outbound leg while said other partyissues said in-band control signals to said network switch.
 21. In atelecommunication system having a network switch capable ofindependently controlling inbound and outbound call legs, a method ofredirecting in-band control of signaling pertaining to a call placed bya calling party, comprising: routing said call from said calling partyto another party through said network switch, said call thereby havingan inbound leg from said calling party to said network switching andoutbound leg from said network switch to said other party; treating saidoutbound leg of said call as a second inbound leg from said other partyto said network switch; monitoring in-band control signals received fromsaid other party via said second inbound leg, thereby allowing saidother party to issue said in-band control signals to said networkswitch; and allowing said calling party to monitor said outbound legwhile said other party issues said in-band control signals to saidnetwork switch.